文档介绍：摘要本文研究区位于新疆克孜勒塔格东北一带,属于北山裂谷构造带西段。北山裂谷构造带是在塔早木原始陆核基础上发展起来的,北邻那拉提一红柳河缝合带,南接敦煌地块。构造带内断裂发育,岩浆活动强烈,地层包括了早元古代变质结晶基底、中元古代沉积盖层、晚古生代裂谷沉积盖层。变质结晶基底一北山岩群是早元古代围绕陆核和陆核间出现的浅海环境下沉积的一套以火山岩为主夹少量成熟度低的碎屑岩经多期变质作用而成的成层无序地层。北山岩群主期变质作用是兴地期(1 800Ma)中压角闪岩相变质作用,变质温度580—650。C、—;主期褪变质作用是阿尔金期(1400Ma)绿帘角闪岩相变质作用,变质温度350—550。C、-,500"C左右温度可能是其主褪变质作用发生的主要温度。到了晚古生代,北山裂谷再次开始了拉张一闭合的演化,并伴随了大规模的火山喷发和岩浆侵位,使北山裂谷构造带内的地温梯度升高,在靠近侵入体的位置发生了接触变质作用,接触变质作用产生了排列不定向的片状黑云母。裂谷闭合收缩挤压和印支一喜山期动力作用及后期剪切作用影响使得北山岩群中的各期侵入岩体发生了碎裂岩化和糜棱岩化。中元古代沉积盖层一古硐井岩群是浅海一滨海环境沉积的一套以沉积岩为主夹有少量凝灰岩的经变质作用而形成的一套成层无序的地层,其变质作用是北山岩群发生主褪变质作用的阿尔金期变质作用,温度压力要稍低于北山岩群。晚古生代裂谷沉积地层有下石炭统红柳园组、上石炭统石板山组和胜利泉组、于泉组及中二叠统骆驼沟组,其中红柳园组、石板山组、胜利泉组、干泉组为北山裂谷构造带在晚古生代早石炭世第一次拉张一晚石炭世闭合期间所沉积,骆驼沟组为中二叠世第二次收缩闭合期间所沉积。关键词:北山裂谷,结晶基底,沉积盖层,地质演化 Abtract The area bestudied inthisdissertation located atthenortheast ofKeziletage inXinJiang,it is a part ofthewest Beishan riftvalley structure riftvalley structure beltdeveloped inTalimu landcore,it’S north neighbour isNalati-Hongliuhe suture beltandthesouth one is Dunhuang are alotofruptures and magma rocks stratum includes early proterozoic era metamorphic crystal basement、middle proterozoic era sedimented cover layer and laterPaleozoic era riftvalley sediment. Metamorphic crystal basement—Beishan rock group are stratified but out oforder layers, which lavaand fewjuvenility elasticrock were sedimented in shallow sea around orbetween the earlyproterozoic era period metamorphism ofBeishan rock group is Xingdi period(1800Ma)middle press hornblende facies,the temperature ofthisfaciesis 580-680。C,and press — offademetamorphism isAerjin period,its temperature is350—550。C and press - 500。Cmaybe themostlytemperature ofMainperiod laterPaleozoic era,Beishan valleydeveloped from craze tolose,at thesame time,lots ofvolcanoes broken forthand lavaup invaded,what makes ground temperature grads hoist,rocks nearby lava occurr